Crisis threatening now the lives of thousands of American children facing a deadly cancer a cancer that can be cured with a drug that tonight. Is in short supply hospitals are now rationing the drug some have already run out of it. Our chief health editor doctor Richard -- been tracking this slow motion crisis for more than a year now tonight the drug shortage affecting the lives of children. This time its share. Hospitals tonight rationing the drug that is curing nine year old Jacob Andrew of leukemia. It's very important for my -- to have distracted saved its life its winning the war. Jacob was diagnosed nine months ago forty years ago it would have been the Jetsons. Method Trixie teens if we lose method tracks. Then we're telling families. We may lose their children. The drug to the most common form of childhood leukemia who works like magic. Close to 90% of children -- There is no alternative. We're getting reports. From across the country right now of hospitals. With supplies that may last days to a few weeks why the shortage. For companies which make the low profit generic drugs have said he production problems -- can't meet demand and -- make more when they can. The FDA monitors drug shortages. How worried are you about this mean is it too late to -- children dying. We're extremely -- about. That's our top priority right now as for Jacob he needs just two more -- since then he's in the clear. Other children may not be so lucky. In rich joins us now you've been appointed many of these pharmaceutical companies don't make a lot of profit on this because -- its generic drug. But you're really concerned here about the lives of children. Hanging in the balance you know I'm really word FDA's racing to find sources overseas they're racing to get manufacturers to increase production. I don't know if they're getting it done in time in the hospitals like puck into becoming their very word. Tipped off on this report and people should keep the tips coming in virtual stay on this thank you.

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